Sage Stossel grew up in a suburb of Boston and attended Harvard University, where she majored in English and American Literature and Languages and did a weekly cartoon strip about college life, called "Jody," for the Harvard Crimson. From 2004 to 2007, she served as Books Editor of the Radcliffe Quarterly

After college she took what was intended to be a temporary summer position securing electronic rights to articles from The Atlantic's archive for use online. Intrigued by The Atlantic's rich history and the creative possibilities in helping to launch a digital edition of the magazine on the Web, she soon joined The Atlantic full time. As the site's former executive editor, she was involved in everything from contributing reviews, author interviews, and illustrations, to hosting message boards and producing a digital edition of The Atlantic for the Web.